During pregnancy, yep, the mother gains one maybe two cups not after.
After giving birth and breast-feeding the breast goes back to his "natural" size.
There is close to none gain after pregnancy ( maybe half a cup at outmost), unless the person gains significant weight.
nope you are wrong, boobs are wut?
mostly FAT and very sensitive to water retention (females have more issues with it than males thx to our hormones) also some lymphatic glands are next to the mammal glands (armpits area) and muscle tissues of the chest if they are too big can change the shape and size of them too (look at the shemale doing too much weight lift, they lose their boobs because of the muscle gain and fat loss + some are obviously taking steroids aka male hormones), when you stop breastfeeding you just stop producing milk but it doesn't mean automatically that the boob size will decrease.
we can gain 1 cup or more when we are ovulating (the luteal phase is a massive hormones release = boobs size increase) and lose it when our periods are over (low levels of hormones during the follicular phase = boobs are at their tinier size of the cycle), i have that issue every month nothing weird or fake here.
all these stuff can change a woman boobs during her entire life: body weight, fat %, water retention, hormones levels, lymphatic system efficiency, glands issues, muscle mass, pregnancy, breastfeeding, ovulation, prescription drugs, contraceptive, diet etc